Probiotic micro-organisms are micro-organisms which beneficially affect a host by improving its intestinal microbial balance (Fuller, R; 1989; J. Applied Bacteriology, 66: 365-378). In general, probiotic micro-organisms produce organic acids such as lactic acid and acetic acid which inhibit the growth of pathogenic bacteria such as Clostridium perfringens and Helicobacter pylori. Consequently, probiotic bacteria are believed to be useful in the treatment and prevention of conditions caused by pathogenic bacteria. Further, probiotic micro-organisms are believed to inhibit the growth and activity of putrefying bacteria and hence the production of toxic amine compounds. It is also believed that probiotic bacteria activate the immune function of the host.
Therefore there is considerable interest in including probiotic micro-organisms into foodstuffs. For example, many fermented milk products which contain probiotic micro-organisms are commercially available. Usually these products are in the form of yogurts and an example is the LC1.RTM. yogurt (Societe des Produits Nestle SA). Several infant and follow-up formulas which contain probiotic micro-organisms are also commercially available; for example the BIO NAN.RTM. formula (Societe des Produits Nestle SA).
Similarly, for animals, there has been interest in including probiotic micro-organisms into animal feeds. For example, Russian patent 2018313 discloses a powdered, spray-dried animal feed which is based upon milk and which contains certain bifidobacteria and streptococci. The animal feed is aimed primarily at live stock although it is mentioned that the feed may be fed to pets.
However, there are two main issues in incorporating probiotic micro-organisms into foodstuffs. First, the foodstuff must be in a form which is palatable to a consumer. Secondly, the probiotic micro-organism must remain viable during storage. The second issue is particularly problematic for ready-to-eat cereal products. These cereal products, unlike fermented milks, are required to have long storage lives; for example at least a year while the cell counts for many probiotic micro-organisms may fall away completely within one or two days. This is particularly the case if the water activity of the foodstuff is above about 0.5. This is usually the case for dried pet foods.
Therefore there is a need for a ready-to-eat cereal product which contains a probiotic micro-organism, is highly palatable, and which is storage stable.